War: A History in 100 Battles. Richard Overy

available to Cuba’s dictator, Fulgencio Batista, but they prevailed in large part because the government forces they faced suffered from a loss of morale in the face of widespread popular hostility to the regime and the crumbling confidence of the dictator himself.

      Technical or moral factors can play an important, even decisive, part in tilting the balance back when, on paper, forces seem unevenly matched. This phenomenon is common in the development of asymmetric warfare during the course of the twentieth century, in which a notionally powerful state finds itself unable to bring that power to bear effectively against an elusive or determined enemy. This imbalance was evident in the struggles to liberate areas from colonial rule or post-colonial dictatorship. French failure in Algeria and Vietnam in the 1950s, for example, was not a product of military weakness in any formal sense, but a result of popular hostility to colonialism and growing uncertainty among the French people about whether empire was any longer worth the military cost of defending it. The United States has enjoyed the world’s largest military budget for decades, but that has not made it any easier to project that power in Vietnam or Somalia, or in the ‘war on terror’ in Afghanistan. Here, too, the odds against smaller and less sophisticated forces can be compensated for by a variety of factors that inhibit the full exercise of power by the dominant state. It is possible to be too powerful as well as too weak. Nuclear weapons might well have transformed the war in Vietnam but they were unusable given the prevailing political situation; drone strikes are supposed to wear down the resistance of Al Qaeda but they have failed to halt the terrorism and invite wide condemnation. The 4,000-year history of battles shows that an apparently weaker or outnumbered force can, under the right circumstances, achieve much against the odds.

       17. THERMOPYLAE AND SALAMIS

      August 480 BCE

      The Greek victory over the vast invading army and navy of the Persian emperor Xerxes in the late summer of 480 BCE is one of the great legends of the classical world. The famous 300 Spartans at Thermopylae, led by their king, Leonidas, has for centuries been a model for courage and discipline seldom exceeded in the modern age – and is now the subject of a blockbuster film. Though this was a battle lost, it was a costly victory for the Persians, and almost immediately following it, the huge Persian fleet, three times the size of the combined Greek vessels, was shattered at the great naval battle of Salamis. Greek independence was saved and Persia finally pushed back into Asia.

      The odds were stacked overwhelmingly in the Persians’ favour, for Xerxes could mobilize the soldiers and ships of his many vassal states. The Greek chronicler Herodotus, writing some forty or fifty years after the battles, numbered the Persian army at 1,700,000. Modern calculations suggest 180,000, including camp followers, and perhaps 130,000 soldiers, marines and sailors in a fleet that Herodotus numbered at 1,207 vessels, a figure more readily accepted today than his statistics on the army. The Greek alliance – those city-states in the peninsula not yet vassals of Persia – could muster only a fraction of this manpower, though in general they were more heavily armed and armoured than Persian soldiers. The Greeks depended on a navy that was for the most part newly built. The Athenian leader Themistocles had persuaded the citizens to use rich new supplies of silver, discovered at the mines of Laurium, 60 kilometres (40 miles) from Athens, in 483 BCE, to fund the building of a large fleet of trireme ships to guard against a Persian invasion. Athens had around 200 triremes by the time Xerxes began the invasion three years later; the rest of Greece supplied perhaps 170–80 ships.

      Xerxes’s strategy was simple. He would march his huge army into Greece, supported and supplied on the seaward flanks by his fleet, until he had defeated any city-state not sensible enough to send him the gifts of water and earth indicating submission. Unlike the failed invasion at Marathon ten years earlier, Xerxes bridged the Hellespont at the modern Turkish Straits so that his army could march overland to its objective. The Greeks met in council at Corinth in 481 BCE to decide their strategy. The Spartans and Corinthians favoured defending at the Isthmus of Corinth to guard the Peloponnesian peninsula. Themistocles, his arguments reinforced by a brand-new fleet, argued that the Persians could easily envelop the defending Greeks by landing troops from their fleet behind them. His strategy was to find a site further north to halt the Persian army while the Greek fleet engaged the Persians and cut off the army’s source of supply. With reluctance the others agreed, though the Spartan king would only take 300 men with him as they sailed north.The Persians swept into Macedonia and Thessaly in the summer of 480 BCE and marched south towards Athens. The Greek army, around 10,000 men, withdrew to the pass at Thermopylae, only 15 metres (50 feet) wide at its narrowest point, and the only road south for a large army. The Greek fleet positioned itself at Artemisium on the flank to keep the Persian ships away. A sudden gale on 26 August wrecked between 200 and 400 of the Persian ships, which were lighter and less seaworthy than Greek ships. The two fleets clashed inconclusively on 30 August, but according to Herodotus, a second gale that night scattered and destroyed more of the Persian ships.

      That same day, the Persian army tried to break through at Thermopylae, only to find that the few thousand Greeks, with the 300 Spartans at their core, could hold the narrow pass with their longer spears and heavier armour, while the Persian archers could not find room to manoeuvre effectively. But on 31 August, Xerxes was told of a narrow gorge that led through the hills beside Thermopylae and dispatched his 10,000 crack troops, the ‘Immortals’, to navigate the path and attack the Greeks from the rear. Leonidas sent most of his forces south to escape destruction, and with just 1,400 men he came out for a final battle with the vast Persian army. They all died where they stood, fighting, according to Herodotus, with ‘their hands and teeth’ when their swords and spears were lost.

      Themistocles received news of events at Thermopylae in the camp at Artemisium, and ordered the fleet to sail south at once. They arrived a few days later in the straits by the island of Salamis, which lay opposite Athens and the Piraeus. Xerxes’s army marched through Attica, sacked Athens, and reunited with the Persian fleet at the city’s port. The Greek allies argued about the next step: the Spartans, whose admiral Eurybiades commanded the fleet, wanted to withdraw once again to the Peloponnese; Themistocles pointed out that this would allow the Persians to land forces wherever they wanted and insisted on staying at Salamis to engage the enemy fleet. Themistocles won the day and the outcome at Salamis showed that his strategic thinking, as the Athenian historian Thucydides later wrote, ‘displayed genius in the most unmistakable way’. Yet arguments between the Greek allies continued until, on 23 September, the Persian fleet arrived at the mouth of the narrow Salamis Strait.

      The ancient accounts do not make clear why Xerxes sought a battle when the Greek fleet could have been blockaded. Modern views suggest that the Persian emperor wanted to avenge the losses to his fleet by one decisive battle that would salve his pride. On the day of Salamis, he set up a throne on Mount Aegaleus overlooking the strait to watch what he expected to be a decisive victory. The Greeks still had an estimated 360 ships. The Persian fleet, though still vastly greater, now contained only an estimated 600–800 vessels after the earlier losses. The Persians drew up the fleet in three ranks on a north-south axis in open sea, but the ships then had to turn sharply to the west to enter the narrow straits in much smaller lines, and here their numerical superiority was no longer an advantage – it was the naval equivalent of Thermopylae. The Greeks, according to the chronicles, sang a paean before they sailed, which put the stakes clearly before them: ‘Forward sons of the Greeks … Now is the fight for everything.’

      The details of the battle itself remain frustratingly sketchy. To encourage Xerxes to attack, Themistocles sent a messenger to the Persian camp with false news that the Greeks were intending to flee, but the lines of Greek ships, drawn up north to south across the narrow channel, instead did the equivalent of what Leonidas’s Spartans had done, luring the Persian ships on, then moving out to ram and board them. The disadvantage of greater numbers soon became evident. The Persian ships crashed into each other, lost formation, and even, it seems, attacked each other in error. It is possible to picture the water full of a mess of drowning men, capsized ships, the debris of broken oars, the wounded and dying. The heavier Greek vessels were at an advantage when it came to ramming, while their more heavily armed marines could be deployed more